马甲竹 ma jia zhu

Bambusa lixin Hsueh & T. P. Yi; B. nutans Munro subsp. cupulata Stapleton.

Culms 8–20 m, 5–7 cm in diam., basally very straight, apically slightly drooping; internodes 40–46 cm, initially white powdery; wall thick; nodes flat, basal several with rings of gray-white silky hairs above sheath scar and with aerial roots; branching from basal node up. Branches several to many, clustered, central 3 dominant, lower branches bent downward, middle branches horizontal. Culm sheaths deciduous, convex, thickly leathery, initially white powdery, densely deciduously stiffly black strigose, later dark brown strigose, margin ciliolate, apex asymmetrically triangular; auricles obviously unequal, strongly undulate and wrinkled, larger ones conspicuously slanted downward to 1/3 of height of sheath, narrowly reniform or obovate-lanceolate, 4.5–5 × ca. 1.5 cm; oral setae curved; ligule 1.5–2 mm, entire, glabrous or very shortly ciliate; blade deciduous, nearly symmetrical, broadly triangular-ovate and acuminate, base broadly cordate and inflated, extending to both sides to join auricles for 1–1.3 cm, base ca. 5/8 as wide as sheath apex, abaxially glabrous, adaxially strigose or scabrous. Leaf blade broadly linear to linear-lanceolate, 15–20 × 1.5–2.5 cm, abaxially pale green, densely pubescent, adaxially glabrous or sometimes hispidulous near base. Pseudospikelets solitary or 2–5 clustered at each node of flowering branches. Spikelets linear to linear-lanceolate, 2.5–7.5 × ca. 0.5 cm; florets 4–6, apical 1 or 2 sterile; rachilla segments clavate, striate, apex ciliate. Glumes 1 or 2, many veined, apex acute; lemma ovate to oblong, 1.2–2.5 × ca. 0.8 cm, glabrous, many veined, margin ± slightly ciliate, apex acute or acuminate and finely tipped; palea slightly shorter than lemma, keels ciliate, 5–7-veined between keels, apex penicillate; lodicules 3, ca. 3.8 mm, anterior 2 thickened at base, 5-veined, margins long ciliate, posterior 1 not thickened at base. Anthers purplish red, 7.5–10 mm, apex obtuse or emarginate. Ovary obovate or ovate-ellipsoid, apex thickened and long hispid; style very short, long hispid; stigmas 3. Caryopsis ellipsoid, ca. 7.5 mm, apex long hispid.

Open fields, riversides, around villages. Guangdong, Guangxi, SE Xizang [Bangladesh, Bhutan, India, Myanmar, Nepal].

Bambusa teres is not recognized as a separate species in S Asia, where the name B. nutans subsp. cupulata is used instead, partially because the name B. teres was long overlooked, while this bamboo became widely known as B. nutans, the type of which, from Kathmandu in Nepal, represents a contiguous allopatric, very similar bamboo from the western Himalayas to E Nepal. The inclusion of B. lixin requires critical investigation.

This species was treated as Bambusa tulda in FRPS (9(1): 80. 1996).